title: Detection of an extended human volatome with comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry.
abstract: BACKGROUND
  Comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GCxGC-TOF MS) has been proposed as a powerful new tool for multidimensional analysis of complex chemical mixtures. We investigated GCxGC-TOF MS as a new method for identifying volatile organic compounds (VOCs) in normal human breath.
  
  
  METHODS
  Samples of alveolar breath VOCs and ambient room air VOC were collected with a breath collection apparatus (BCA) onto separate sorbent traps from 34 normal healthy volunteers (mean age = 40 yr, SD = 17 yr, male/female = 19/15). VOCs were separated on two serial capillary columns separated by a cryogenic modulator, and detected with TOF MS. The first and second dimension columns were non-polar and polar respectively.
  
  
  RESULTS
  BCA collection combined with GC×GC-TOF MS analysis identified approximately 2000 different VOCs in samples of human breath, many of which have not been previously reported. The 50 VOCs with the highest alveolar gradients (abundance in breath minus abundance in ambient room air) mostly comprised benzene derivatives, acetone, methylated derivatives of alkanes, and isoprene.
  
  
  CONCLUSIONS
  Collection and analysis of breath VOCs with the BCA-GC×GC-TOF MS system extended the size of the detectable human volatile metabolome, the volatome, by an order of magnitude compared to previous reports employing one-dimensional GC-MS. The size of the human volatome has been under-estimated in the past due to coelution of VOCs in one-dimensional GC analytical systems.
authors.affiliation: Breath Research Laboratory, Menssana Research Inc, Newark, New Jersey, United States of America ; Department of Medicine, New York Medical College, Valhalla, New York, United States of America.
authors.forename: Michael
authors.initials: M
authors.lastname: Phillips
authors.forename: Renee N
authors.initials: RN
authors.lastname: Cataneo
authors.forename: Anirudh
authors.initials: A
authors.lastname: Chaturvedi
authors.forename: Peter D
authors.initials: PD
authors.lastname: Kaplan
authors.forename: Mark
authors.initials: M
authors.lastname: Libardoni
authors.forename: Mayur
authors.initials: M
authors.lastname: Mundada
authors.forename: Urvish
authors.initials: U
authors.lastname: Patel
authors.forename: Xiang
authors.initials: X
authors.lastname: Zhang
mesh_terms: D000328:Adult; D001944:Breath Tests / Q000379:methods*; D045853:Exhalation; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D055549:Volatile Organic Compounds / Q000032:analysis*
chemical_list: D055549:Volatile Organic Compounds